Example 2
Stanley planted a tree in his backyard. The manager of the plant nursery he purchased it from told Stanley that the tree would double in height every 4 years. If Stanley’s tree started out only 1.5 feet tall, how tall will it be in 20 years? Write an exponential equation of the general form , where is the initial value, is the base, is the time, and is the final value. Then use it to solve the problem.